Appearance: White Or Off-white Powder, Odorless, Tasteless, And Non-toxic Magnesium Oxide

Magnesium oxide, with the chemical formula MgO, is an inorganic compound and also an oxide of magnesium. It is a white solid at room temperature. The following is a detailed introduction to magnesium oxide:
1. Physical properties
Appearance: white or off-white powder, odorless, tasteless, and non-toxic.

Melting point: 2852℃ (some data also mention 2830℃, but 2852℃ is generally considered to be more accurate).

Boiling point: 3600℃.

Density: 3.58g/cm³ (25℃).

Solubility: Very slightly soluble in water, insoluble in alcohol, but soluble in acid and ammonium salt solutions. Solubility in water increases with increasing temperature and is also affected by the presence of carbon dioxide.

Other properties: Strong refraction in the visible and near-ultraviolet range; high resistivity; good stability, but incompatible with bromine trifluoride, bromine trichloride, phosphorus pentachloride, etc.

2. Chemical properties
Alkaline oxide: It has the general properties of alkaline oxides and can react with acids to form salts and water.

Reaction with water: It reacts slowly with water to form magnesium hydroxide, but the reaction can be accelerated under certain conditions.

Reaction with carbon dioxide: When exposed to air, it easily absorbs water and carbon dioxide and gradually becomes basic magnesium carbonate.

3. Production method
The raw materials for the production of magnesium oxide mainly include magnesite (MgCO₃), dolomite (MgCO₃·CaCO₃) and seawater. The main production methods include:

Thermal decomposition method: Magnesium oxide is obtained by thermal decomposition of magnesite or dolomite.

Seawater method: Treat seawater with slaked lime to obtain magnesium hydroxide precipitate, and then burn magnesium hydroxide to obtain magnesium oxide.

Brine method: Use magnesium chloride brine blocks obtained from the comprehensive utilization of seawater or brine after bromine extraction as raw materials, add sodium hydroxide or sodium carbonate to generate magnesium hydroxide or basic magnesium carbonate precipitate, and then burn to obtain magnesium oxide.

4. Product types
Magnesium oxide products are mainly divided into light magnesium oxide and heavy magnesium oxide:

Light magnesium oxide: loose volume, white amorphous powder. Low density, large specific surface area, strong adsorption. It can be used in catalysts, rubber fillers, flame retardants for building materials, pharmaceutical antacids and other fields.

Heavy magnesium oxide: compact volume, white or beige powder. It has high density, small specific surface area, is not easy to decompose when heated, and has low chemical activity. It is mainly used for high-temperature refractory materials, manufacturing refractory crucibles and furnace lining adhesives, etc.

5. Application fields
The application fields of magnesium oxide are very wide, including but not limited to the following aspects:

Industrial field: used for the production of magnesia products, advanced lubricating oil processing, silicon steel grade applications, advanced electromagnetic grade applications, etc.

Medical field: as antacids and laxatives, used to treat hyperacidity and duodenal ulcers, etc.

Food field: used for food additives, color stabilizers, pH regulators, etc.

Other fields: It can also be used in industries such as ceramics, enamel, glass, dyes, etc.; as a raw material for optical coatings; used in anti-slip powder for competitive gymnastics, baseball pitchers, rock climbing and other sports, etc.

6. Safety

Although magnesium oxide has important applications in many fields, its safety should also be taken into consideration during use. For example, inhaling magnesium oxide fumes can cause metal fume disease, so protective measures should be taken when using it. At the same time, the storage conditions of magnesium oxide must also comply with relevant regulations to ensure its stability and safety.